*
*=== Opphst ===========================================================*
*
*----------------------------------------------------------------------*
*                                                                      *
*     Copyright (C) 2003-2019:  CERN & INFN                            *
*     All Rights Reserved.                                             *
*                                                                      *
*     OPtical PHoton STack:                                            *
*                                                                      *
*     Created on 19 September 1997 by    Alfredo Ferrari & Paola Sala  *
*                                                   Infn - Milan       *
*                                                                      *
*        wtopph = weight of the photon                                 *
*        poptph = laboratory momentum of the photon in GeV/c           *
*        xoptph = x-coordinate of the photon                           *
*        yoptph = y-coordinate of the photon                           *
*        zoptph = z-coordinate of the photon                           *
*        txopph = direction cosine of the photon                       *
*                 with respect to x-axis                               *
*        tyopph = direction cosine of the photon                       *
*                 with respect to y-axis                               *
*        tzopph = direction cosine of the photon                       *
*                 with respect to z-axis                               *
*        txpopp = direction cosine of the photon polarization          *
*        typopp = direction cosine of the photon polarization          *
*        tzpopp = direction cosine of the photon polarization          *
*        donear = distance to the nearest boundary                     *
*        agopph = age of the photon (seconds)                          *
*        cmpopp = total path length of the photon (cm)                 *
*        anfopp = extra infos: for EM particles a non zero value is    *
*                 the kinetic energy a possible delta ray parent       *
*                 (excluding Moller and Bhabha)                        *
*        ekpopp = kinetic energy of the parent of the last (hadronic)  *
*                 inelastic interaction                                *
*        loopph = generation of the photon                             *
*        louopp = user flag                                            *
*        nregop = number of the region of the photon                   *
*        nlatop = number of the lattice cell of the photon             *
*        tpropp = kinetic energy of parent particle of the photon      *
*        apropp = age of the parent particle of the photon (seconds)   *
*        ipropp = id (paprop) of the parent particle of the photon     *
*        lpropp = generation of the parent particle of the photon      *
*        infopp = extra infos: for EM particles a non zero value is    *
*                 the (coded) id of a possible delta ray parent        *
*                 (excluding Moller and Bhabha)                        *
*        lnfopp = extra infos: for EM particles a non zero value is    *
*                 the generation of a possible delta ray parent        *
*                 (excluding Moller and Bhabha)                        *
*        iazopp = id of a possible radioactive isotope parent          *
*        ipiopp = (Paprop) id of the parent of the last (hadronic)     *
*                 inelastic interaction                                *
*        npropp = # of the primary track which generated the photon    *
*                 (not used for the moment)                            *
*        lstopp = stack pointer                                        *
*        lmxopp = highest value of the stack pointer encountered       *
*                 in the run                                           *
*                                                                      *
*----------------------------------------------------------------------*
*
      INTEGER*8 NLATOP
      COMMON / OPPHST /               WTOPPH (MOSTCK), POPTPH (MOSTCK),
     &               XOPTPH (MOSTCK), YOPTPH (MOSTCK), ZOPTPH (MOSTCK),
     &               TXOPPH (MOSTCK), TYOPPH (MOSTCK), TZOPPH (MOSTCK),
     &               TXPOPP (MOSTCK), TYPOPP (MOSTCK), TZPOPP (MOSTCK),
     &               DONEAR (MOSTCK), AGOPPH (MOSTCK), TPROPP (MOSTCK),
     &               APROPP (MOSTCK), CMPOPP (MOSTCK), ANFOPP (MOSTCK),
     &               EKPOPP (MOSTCK),           SPAROK (MKBMX1,MOSTCK),
     &               NLATOP (MOSTCK),           ISPORK (MKBMX2,MOSTCK),
     &               LOOPPH (MOSTCK), LOUOPP (MOSTCK), NREGOP (MOSTCK),
     &               IPROPP (MOSTCK), INFOPP (MOSTCK), LNFOPP (MOSTCK),
     &               IAZOPP (MOSTCK), IPIOPP (MOSTCK), LPROPP (MOSTCK),
     &               NPROPP (MOSTCK), LSTOPP, LMXOPP
      SAVE / OPPHST /